Scorpion, Yanmar, Mercruiser

vlad · 02 February 2007, 19:32

Hi all,
I am completely fed up with the Yanmar-Bravo 3-they all break apart at the end combina tion, and still trying to find a solution...

I am now on my second leg replacement on my Scorpion 8.75, and I know people that are curently on their third Bravo 3, and under 1000 hrs of operation, but I cant afford some alternative but pricey drives such as surface etc.

I won't get into much detail as I know from previous posts that many are aware of the problem, the reason I write here is to ask for advice whether replacing Bravo 3 with Bravo 1 would be a reasonable alternative , Bravo 1 being more reliable but probably not excellent in handling and manoevrability.

any comment will be valuable

Dieselroy · 02 February 2007, 21:08

Hi Vlad!

Has done 420 hours so far on our Tornado 9,5 with 320 Mercruiser and
Bravo one XR diesel 1:50, and we have a Bravo on 26" prop.

So far everything looks fine, changed the oil on the drive every 100 hours,
Can for sure drive longer, but changes it for safety..

Our boat is very manouverable and works fine with the bravo one.

The reason i think is the small propeller wich spins as the turbo comes in and there is not so much torque on the propeller.

We are also very carfull when having airtime and pulls the throttle off befoe we hit the water.

Try a bravo one and see how it works on your boat.

Best wishes
Roy

Dieselroy · 02 February 2007, 21:10

by the way, what speed do you get on your boat?

vlad · 02 February 2007, 21:27

Its good to hear that you still have good manoevrability with the Bravo one.
I am going to try a B1 when it will become available in a couple of months and excange my new B3 for it if I find it satisfactory.

My RIB is quite heavy, top speed just under 40 knots.Some claim B1 to be faster than the B3, while some in this forum say its slower....

Why did you go for the Bravo 1 leg? But of course you have Mercruiser..dont know if they have the same problems everybody seems to have with the YANMAR combination.

Brian · 03 February 2007, 16:06

Huh. Only third Bravo in under 1000 hours!!
What luxury!

Try 5 in under 700 hours!!

Eventually I found that the problem was a misaligned engine. Alignment is absolutely critical.

Bravo 1s and 2s (I have tried them all!) will do you no good anyway, even if your engine alignment is fine. Changing to either of them will kilter your boat to port and this is only just about correctable by trim tabs. No good as a long term solution.

1s and 2s also severly reduce your topspeed regardles of propping.

BogMonster · 03 February 2007, 19:32

Just a question by somebody who knows nothing about sterndrives, but why are they all rubbish? There are loads of posts on here about problems, surely there must be a market for a sterndrive that isn't made of cheese?

Dieselroy · 04 February 2007, 17:43

Hi again.

Our boat is quite heavy too, weighs about 2200 kg.
Max speed we have seen is 48 knots.

There is no problem with the torque kilting our boat to port.
Maybe its because of the weight.

I think you will have to try and change drive and find out because no boats are alike and testing is the only way to find out.

I would guess you could have the same drive/propeller combo as we have.

remember also that the Yanmar throws out alot of torque when it starts.
One propell and small as we have it will spin and not cause so much torque when you start, as rhe bravo 3 does . somewhat like a clutch.

good luck

vlad · 04 February 2007, 17:56

Brian, I have cruised -around your waters (guernesey)- on a 275 HP Mercruiser Bravo 1 powered Rib, and surely this boat she had a tendency of leaning to the port side... But the boat was much smaller (5.5m) and lighter..I wander if Dieselroy has the same leaning problem.

To me safety should be first at sea, so if I could correct everything using trim tabs why not?I am just tired of that when-it-will-break-again-feeling.
Actually I was going to install tabs anyway..I feel the boat needs them.

Conserning the speed, some people insist Bravo 1 is much faster, while others in this forum say it's slower than the B3...

My problems whith the outdrives did not come from faulse alignement...I am no expert in fiting engines but I know a lot of people with Bravo3 failures.Unless nobody can align an engine properly here in greece...(which is a serious possibility by the way!)

And Stephen, thats a good question...if you find one, I'll be the first to buy it.

vlad · 04 February 2007, 18:02

Thank Dieselroy!I just posted the question but seems that you answered before even reading it. GOOD TIMING

Dieselroy · 04 February 2007, 19:15

Hi again.
Probably a bravo 1 is faster, but unless speed is your first goal, i think the overall performance counts most.

Also if you have a smaller propell it will not lean so much to the side.

We have tried both 24" and 28" bravo propeller but ended up with a 26".

Aligning your engine is easy if you have the right tool.
every mercruiser workshop should have one.

A good solution for tabs is looking at Volvo.

Whats the weight of your boat? seems you lack a lot fo speed

Roy

vlad · 07 February 2007, 14:10

Well, speed alone is not my goal but I consider it "healthy" for a boat to be capable of at least 40 knots.

The boat ,having a "mediterrannean" configuration, that is,aft sunbeds with lockers underneath,full length sunbed covered engine room,big capacity tanks etc, is certainly on the heavy side specially when in the water for long periods in the summer, with every available space full of lugagge,tents,and a big deck fridge!

I am not sure of the exact weight when in "expedition" load.
But its pretty much always like this!!

Your advice with the small prop sounds good I will definately give it a try.

Vlad